Joe Maddon says Cubs hitters are feeling “a little bit French-fried mentally,’’ and they didn’t do much to disprove that theory in a 2-1 loss to the Reds on Sunday.

Willson Contreras, in particular, looked in need of a clearer head after blasting the ball as a pinch hitter in the fifth inning. He flipped his bat and stood at home plate watching it fly into the baby-blue sky, apparently thinking it was going to land on Sheffield Avenue. Instead it hit the center-field wall.

While it was the biggest of five hits for the Cubs, the lack of optimal baserunning from both Contreras and Addison Russell may have cost the Cubs a run in game they lost by one.

“Horrible,’’ Maddon said of Contreras’ lapse. “I didn’t like that at all. That will be addressed. The whole team didn’t like that.’’

Contreras is hitting .220 with only two homers since his trip to the All-Star Game and lately has been getting more bench time than usual, with Victor Caratini emerging from the shadows. Contreras was pinch hitting for Jose Quintana in the fifth inning and thought he’d found vindication when he hit a first-pitch slider from Jose Castillo (10-12).

He knew he’d screwed up when Billy Hamilton played the ball off the top of the wall.

“I thought it was gone,’’ Contreras said. “I hit it super good. … Thank God I was able to run hard and make it to second base because what I did was not good for baseball, and a lot of people were watching me.’’

Contreras apologized to Castillo later in the inning and understands he let down his teammates.

“It was bad,’’ he said. “I’m embarrassed with myself.’’

Russell, who was on first with one out, hesitated at second base to watch the ball even after Hamilton turned to play it off the wall. He advanced only to third on the play, so Contreras couldn’t have gotten a triple on the ball even if he had gone full speed.

Albert Almora Jr. followed with a sacrifice fly, scoring Russell and allowing Contreras to reach third. But Contreras was stranded there on an Ian Happ groundout after Anthony Rizzo walked.

The Cubs had another chance to tie the game in the seventh, but lefty Amir Garrett struck out Rizzo with Kris Bryant on third after he and Almora hit back-to-back singles.

Photos from the Cubs' 2-1 loss to the Reds at Wrigley Field on Sept. 16, 2018. (Nuccio DiNuzzo / Chicago Tribune)

Quintana (13-10) took the loss because he allowed solo homers to Scott Schebler and Phillip Ervin, with Schebler’s coming on the first pitch of the game. You don’t really want to play from behind every pitch of a game when it’s your 27th consecutive day with a game scheduled, but that was the case.

The Cubs did get help from the Pirates, who beat the Brewers on Sunday in Milwaukee. The Cubs maintained their 2 1/2-game lead in the National League Central and reduced their magic number in the division to 11.

They travel to Arizona to wrap up an unprecedented stretch of games scheduled on 30 consecutive days. They’ve gone 16-10 in the stretch, with one game lost to a rainout in Washington, which forced the Thursday makeup game in which de facto closer Pedro Strop was injured.

“We’re asking a lot of these guys to play as often, in different cities at different times and in different weather conditions,’’ Maddon said. “It’s not easy. I think what we’ve done is actually pretty spectacular.’’